Engine/Transmission (1998.5 - 2002) SPA Oil Guage Pressure Flucuation

[kscheffler]

I just installed a SPA oil pressure and oil temperature guages via a Tee fitting off the top of the oil filter housing. Seems to work fine for oil temperature but I am getting some pretty wild flucuations on the oil pressure. IDLE = 40 to 45 psi; 1800 rpm will vary from 60 to 83 psi. After running at 2000 rpm and then releasing the throttle I will see pressures as low as 26 psi. The variations do not seem to be normal; or the guage is located in the wrong postion. Where else can I pick up oil pressure? Then maybe these values are correct and the guage is really recording what the oil pump is putting out. Although I find it hard to believe that is would not stablize when running on cruise control. Any thoughts/ideas?? Thanks in advance. PS the new generation SPA guages work great...

 

[BPINE]

Did you put a tee in the feed to the turbo? I just put them where you see the plug on the filter housing next to the feed to the turbo and have had no troubles at all.

 

[kscheffler]

I did install the T on the top of the filter. WHat type of guages are you running. Maybe these SPA's are too sensative? How low of a pressure do you see?

 

[TomGolden]

I have a set of the brand new SPA Series 2 gauges, one of which is oil temp, not pressure. But, my fuel pressure gauge does fluctuate kind of a lot. I am going to reprogram it's sampling rate to a less often rate, say maybe every 1. 0 seconds rather than the current 0. 4 seconds. That may help your situation??



Tom

 

[kscheffler]

Tom

I have thought about that but I would really like to know if these pressure spikes are real or not. What they prefer to have us do is to install a 2 foot piece of hydraulic hose to provide a shock absorber for pressure. I have this on my fuel guage and it works fine. You might want to consider the same for your fuel guage and then remote mount your sender unit. What do you think of your new SPA guages???

 

[BPINE]

kscheffler now I get what you are doing, IMO you will have to slow the sample rate just a bit as Tom said. The SPA gauges pick up a lot of spikes and I think the pressure transducers are a little sensitive. A rubber hose or a snobber might help though.

 

[Bigsaint]

Tom nailed it. Change the display refresh rate from 0. 4 to 1. 0, should cure the jumps in the readings. The SPA will always sample at the 0. 4 rate, but will avg. the psi's and display them at whatever interval you program the display to refresh at, up to 15 or so seconds, if my memory serves me. I had to do the same when I moved my SPA FP sender from pre to post filter, worked great. The thought of a snubber line sure won't hurt, either. My SPA sender isn't snubbed, shame on me I guess, but I'm to the point that I'm curious as to how long it will last without a snubber. It's been post filter for over 1 year now.



I mounted a small 1 1/4" gauge on the frantz filter inlet, which displays approx. the same psi's as the OEM gauge in the cab, so I believe you source location is fine.



Scott W.

 

[kscheffler]

I will reprogram the SPA and see what happens. I still would like to know why it varies so much. I am also going to fine factory pressure sensor and see if I can tee into that location so it is reading the same as the factory. Big variations between the factory guage and the SPA guage. Seems like the factory guage is also averaging over a long period of time... thanks again for the help. . kts

 

[TomGolden]

Re: Tom

Originally posted by kscheffler

What do you think of your new SPA guages???

I love them!! They are awesome!! I haven't even played with them yet, except to reduce their displayed sampling rate, as I already suggested might cure your problem. Haven't even tried using the red background color yet



Tom